Supporting Document 2

Supporting document 2

Assessment of Microbiological Hazards Associated with the Four Main Meat Species

July 2009 amended August 2013

1

Contents

Executive summary i

Background 1

Introduction 2

Purpose 2

Scope 2

Existing assessments 2

Epidemiological evidence 3

1.Cattle production in Australia 5

Introduction 5

Cattle production 5

Abattoir operations 7

Hazard identification 7

2.Sheep production in Australia 22

Introduction 22

Lamb and mutton production 22

Abattoir operations 24

Hazard identification 24

3.Goat production in Australia 30

Introduction 30

Goat production 30

Abattoir operations 32

Hazard identification 32

4.Pig production in Australia 37

Introduction 37

Pig production 37

Abattoir operations 39

Hazard identification 39

Summary 48

Appendix 1: Foodborne disease outbreaks associated with meat 50

1

Executive Summary

As part of Food Standards Australia New Zealand’s proposal to assess whether a Primary Production and Processing Standard for Meat and Meat Products was required, FSANZ identified hazards that may be found in meat, where in the meat supply chain they may be introduced into the animal or the meat and where in the supply chain they may be controlled.

This report identifies hazards (both identified and potential) that may be associated with meat from the four main meat species (cattle, sheep, goats and pigs), and lists pathogenic microorganisms that, if unmanaged, present or may potentially present a risk to public health. The information has been derived from industry data, microbiological analyses and published scientific data. The document does not attempt to document the severity of illness presented by these hazards, nor does it determine the likelihood of their occurrence in the final meat product or characterise the risk they may present. The report does however review meat associated foodborne disease evidence in Australia.

A range of potential hazards have been identified along the production and primary processing chain. Limited, if any, prevalence and incidence data is available for these hazards in meat. Given the lack of epidemiological evidence also available, it would suggest that the likelihood of these hazards causing illness from consumption of meat is quite low.

The principal microbiological hazards associated with the four main animal species are:

Animal / Principal microbiological hazard
Cattle / Pathogenic Escherichia coli, Salmonella spp., Campylobacter jejuni and C.coli,
Sheep / Pathogenic Escherichia coli and Salmonella spp.
Goats / Pathogenic Escherichia coli and Salmonella spp.
Pigs / Salmonella spp., Yersinia enterocolitica and Y. pseudotuberculosis, Toxoplasma gondii, Campylobacter jejuni and C. coli.

During the animal production phase, there are a number of key inputs and activities which influence the manner in which hazards may be introduced or amplified. They are summarised below:

Input and/ or activity / Comment / Step in chain where control may be applied /
Animal Health / Pathogens may exist in the animal with or without exhibiting clinical signs / Animals with clinical signs of disease or illness are identified and managed at:
·  Dispatch from farm/saleyard
·  Arrival at abattoir
·  Ante-mortem inspection
Without clinical signs, potential hazards may be identified and managed at:
· Slaughter to minimise contamination from external surfaces or internal spillage
·  Post-mortem inspection
Stress / Animals may be more susceptible to infection and/or have increased faecal shedding. Pathogens colonise the gut / Minimise exposure of animals to stress during:
·  Transport
·  Lairage
Feed / Feed has the potential to introduce pathogens into the gut or environment / Management of input of manure and fertiliser onto pasture
Control supplements
Oversight of ensilage operations
Water / Contributes to internal and external contamination / Access of animals to suitable drinking water
Environment and management of biosecurity / Pathogens may contaminate external surfaces of animal, or can lead to ingestion or infection of the animal / Pasture management
Vermin and pest control
Good agricultural practices
Sound animal husbandry

During the primary processing stage there are two main sources of contamination to the meat carcass:

·  External contamination: from the animal (hide, skin, fleece, hooves, faeces, etc) and the environment (including personnel), and

·  Internal contamination: during evisceration and dressing operations and where the spillage of gastrointestinal tract contents occurs.

The burden of illness that may be attributed to meat and meat products was assessed by evaluating OzFoodNet outbreak data. Sixty-six outbreaks of foodborne illness associated with meat products in Australia were reported to OzFoodNet between January 2003 and June 2008. More recent data drawn from published OzFoodNet reports[1] indicate 42 meat-associated outbreaks were reported between June 2008 and December 2011. While the data demonstrates the occurrence of outbreaks involving meat, they are usually due to dishes containing a meat product. Attribution to a specific meat source is either limited or difficult to establish with any confidence. Where meat products have been implicated in foodborne illness, generally these were further processed products and the most common causative microorganisms were Salmonella serotypes, Clostridium perfringens and Staphylococcus aureus. The undercooking of meat and temperature abuse after cooking were the major causes of meat-associated outbreaks.

The findings of this assessment are consistent with the significant body of evidence that exists for the Australian domestic meat industry indicating that domestically-reared red meat (cattle, sheep, goats) and pigs, processed under existing standards, present a low risk to public health. Also evidenced is that industry personnel are mature in their knowledge and management of food safety risks.

Considerable data are available to support the safety of meat and meat products produced from beef, sheep and pork in Australia. The evidence suggests that Australian meat from these species has a low microbial load and generally low prevalence of pathogens. Many of the pathogens listed in this assessment occur infrequently or not at all on Australian meat.

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Background

Food Standards Australia New Zealand (FSANZ) has responsibility for protecting the health and safety of consumers through the development of food standards. The FSANZ Act requires FSANZ, when developing or varying standards, to have regard to “the need for standards to be based on risk analysis using the best available scientific evidence”.

The development and application of a Primary Production and Processing Standard for Meat and Meat Products will be dependent on an analysis of the public health and safety risks, economic and social factors and current regulatory an industry practices. The analysis of the public health and safety risks will be based on a comprehensive scientific assessment of public health hazards associated with the consumption of meat.

FSANZ uses a number of methodologies to assess hazards, including risk profiling, quantitative and qualitative assessments and scientific evaluations. The methodology utilised depends on the purpose of the assessment and on the availability, quality and quantity of data.

The assessment will consider all stages in the meat supply chain, from the growing environment through to primary processing. In undertaking the assessment, FSANZ will utilise available information including current microbiological and chemical surveillance data, epidemiological data, consumption data and existing published and unpublished risk assessments from a variety of sources.

Introduction

Purpose

The purpose of this assessment document is to provide a review of the inputs and key stages of the meat supply chain for cattle, sheep, goats and pigs.

In the process of undertaking this work, the following questions are being addressed:

·  What are the factors (including inputs, practices and activities and environmental factors, etc) which influence hazards at each step of the meat supply chain?

·  What are the food safety hazards associated with each factor of the meat supply chain?

The hazards associated with each step in the supply chain are described and listed in a series of tables. The outputs of this evaluation will also facilitate the identification of any significant gaps in knowledge, and assist in identifying the requirement for any further risk assessment work.

Scope

The assessment considers all stages of the meat supply chain, from the animal production environment up to the end of primary processing (ie: post-abattoir carcass or boning room) for the four main meat species; cattle, sheep, goats and pigs.

This assessment will identify both recognised and potential hazards but not food safety-related market access hazards as defined below:

·  Recognised hazards are those where epidemiological data exists to support illness occurring as a result of consuming meat or meat products.

·  Potential hazards are those hazards which may present a food safety risk from consumption of meat and meat products, but where no epidemiological evidence exists.

·  Market access related hazards are those potential hazards related to food safety which are technical requirements to trade, ie: generic E. coli and Total Viable Counts.

Existing assessments

A number of comprehensive scientific assessments have been undertaken in Australia on the microbiological hazards that may be found in the major meat species and the risk posed to consumers from consumption of meat and meat products. These include scientific assessments and risk-profiles generated by Meat and Livestock Australia and Australian Pork Limited.

In 2008, FSANZ commissioned a review of the domestic meat supply chain[2] which indicated that some sectors of the meat industry, such as domestically reared red meat (cattle, sheep and goats) and pigs are fairly mature in their knowledge and management of food safety risks.

Key findings of the report included:

·  Considerable evidence exists supporting the microbiological and chemical safety of meat and meat products from commonly consumed species (beef, sheep and pork).

·  In large part, meat associated outbreaks are a consequence of post cooking contamination or post cooking temperature abuse.

·  The review of quantitative risk assessments indicates that control strategies employed closer to the consumer are more likely to have a direct and major effect on foodborne hazards.

The review notes that a large body of Australian, peer-reviewed work on red meat processing has been published over a number of decades, culminating in three national baseline studies on beef and sheep meat. These include analysis of indicator organisms such as Total Count, Enterobacteriaceae, Coliforms/E. coli, Staphylococcus aureus and the pathogens: Campylobacter, Listeria, Salmonella and Enterohaemorrhagic E. coli (EHEC). State based surveys have also been undertaken focused exclusively on domestic abattoirs and Very Small Plants.

The E. coli and Salmonella Monitoring (ESAM) program provides a database of over 300,000 test results for beef, sheep and pig carcasses processed at export establishments. ESAM data suggests that Australian meat from these species has a low microbial load and generally low prevalence of pathogens.

These Australian peer-reviewed and ESAM data indicate that standards of hygiene during slaughter and processing of beef, sheep and pigs in Australia are at least equal to those of major trading partners and competitors.

Epidemiological Evidence

The public health burden presented by meat and meat products in Australia was determined by examination of the epidemiological evidence assembled by OzFoodNet (Appendix 1).

The OzFoodNet Outbreak Register shows that between January 2003 and June 2008 there were 66 outbreaks associated with meat in Australia. More recent data drawn from published OzFoodNet reports[3] indicate 42 meat-associated outbreaks were reported between June 2008 and December 2011. The majority of outbreaks were due to dishes containing a meat product. Unfortunately attribution to a specific meat source is complex as outbreaks are usually reported as being a result of consuming a “mixed dish”. Where meat products have been implicated in foodborne illness, these were generally further processed product with the causative microorganisms being Salmonella serotypes, Clostridium perfringens and Staphylococcus aureus. Undercooking of meat and temperature abuse after cooking are major factors in outbreaks.

Sources of foodborne illness are determined through epidemiological and/or microbiological analysis during outbreak investigations. Critical for the generation of good data is the ability to quickly identify an outbreak and initiate an investigation in order to attribute illness to a particular food. Difficulties exist because of:

·  Time delays in recognition or notification of an outbreak;

·  Food recall biases when attempting to gather food consumption histories;

·  Long exposure windows for specific pathogens (e.g. Listeria monocytogenes);

·  Reluctance of individuals to participate in investigations;

·  Inability to trace food products to their source;

·  Inability to obtain representative food samples for microbiological analysis; and

·  A lack of precision in methods for sample analysis and pathogen identification.

It is important to recognise that outbreak data only represents a small proportion of actual cases of foodborne illness, as many outbreaks go unrecognised and/or unreported to health authorities. People do not always seek medical attention for mild forms of gastroenteritis, medical practitioners do not always collect specimens for analysis, and not all foodborne illnesses require notification to health authorities. Furthermore, most gastrointestinal illness occurs as sporadic cases with no obvious association with each other, and it can be very difficult to identify a source of infection from an investigation of a single case.

1. Cattle Production in Australia

Introduction

Traditionally, cattle production in Australia has been based upon extensive farming systems, which range from the harsh, dry climates of the north to the cooler, wetter, green pastures of southern Australia. Significant differences exist between climatic and geographical conditions, and on the species of animal grown and the production practices employed. Furthermore, beef production systems are evolving from extensive to semi-intensive and intensive units across the Australian landscape.

The Australian herd is over 28 million head of cattle, which produce around 3 million tonnes of beef and veal per annum (ABARE 2011 figures)[4].

Cattle Production

The organization of beef cattle production in Australia continues to advance, reflecting improved knowledge and changing market demands. Producers are switching to cow-calf operations, producing young cattle for feedlots or the live export trade and reducing production of grass fed animals.

Within the milder climatic conditions of Southern Australia, breeds such as Bos Taurus are grown predominately on pasture in the mountains and plains. While in the north, native pastures such as tropical grasses, scrub land and legumes prevail and these are more suited to breeds such as Bos indicus. Under these conditions cattle graze on extensive open-range holdings. Extensively reared cattle entering the marketplace are generally between 15-24 months of age with average slaughter weight (dressed carcass) in excess of 260kg (ABARE, 2011). The major inputs during production are feed and water, with supplementary feeding at certain times of the year or during drought.